Question: Khan.scratchpad.disable(); Stephanie sells magazine subscriptions and earns $$3$ for every new subscriber she signs up. Stephanie also earns a $$39$ weekly bonus regardless of how many magazine subscriptions she sells. If Stephanie wants to earn at least $$67$ this week, what is the minimum number of subscriptions she needs to sell?
Solution: To solve this, let's set up an expression to show how much money Stephanie will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since Stephanie wants to make at least $$67$ this week, we can turn this into an inequality. Amount earned this week $\geq $67$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $67$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $3 + $39 \geq $67$ $ x \cdot $3 \geq $67 - $39 $ $ x \cdot $3 \geq $28 $ $x \geq \dfrac{28}{3} \approx 9.33$ Since Stephanie cannot sell parts of subscriptions, we round $9.33$ up to $10$ Stephanie must sell at least 10 subscriptions this week.